1. Field of the Invention
The present invention relates to evaporative coolers and more particularly to improved covers for evaporative coolers.
2. The Prior Art
Evaporative coolers operate on the well-known principle of cooling by the evaporation of water. The heat of vaporization is absorbed from the air in contact with the evaporating water. Greater air to water contact is provided by creating air flow through a porous filter pad moistened with water. Most conventional evaporative coolers are box-like and have louvered sides with porous filter pads placed across the louvered openings. Water is percolated over the filter pads while air is drawn through the moist pads by an electrically driven blower. The cool air is then directed into the desired building space by conventional duct systems.
During extended periods of cooler weather, when the cooler is not in operation, it is desirable to seal the cooler to both protect the internal mechanism thereof and to prevent cold ambient air from blowing through duct work into the building. Historically, covers for evaporative coolers have been fabricated from a waterproofed fabric material or plastic sheeting. These materials have proven unsatisfactory as cooler covers for several reasons: (1) the material is subject to rapid deterioration through weathering; (2) the material insufficiently insulates the cooler openings from cold weather; and (3) fabric or plastic sheeting covers tend to flutter or vibrate in wind and transmit a "drumming" sound through the cooler duct work.
In recognition of these shortcomings, certain prior art devices have been proposed. Examples of two such devices are disclosed in U.S. Pat. Nos. 3,006,498 and 3,379,481. These devices include rigid panels hingedly and permanently affixed to the cooler body. It will be noted that both of these prior art devices require that the covering panels remain permanently affixed to the cooler and thereby create additional problems such as being subject to wind damage and restricting air flow to the cooler thereby inhibiting the efficiency of the same.
It would, therefore, be an improvement in the art to provide a completely removable cooler cover and method for sealing an evaporative cooler such that it minimizes wind-induced noise and ambient air penetration. Such a method and apparatus are disclosed by the present invention.